Buderus 800-24 Installation And Servicing Instructions page 47

5.3.4 Check combustion air/flue gas system and hose
connections
Check combustion air/flue gas system for blockages.
5.3.5 Replacing the UBA
Disconnect system from power supply by removing main
fuse or power connection plug.
Swivel the UBA to one side and pull the four-pin plug of the
mains power switch out at the back of the UBA.
Disconnect all plug-in cables. Note the position of each
plug-in cable.
Loosen the three screws on the UBA and remove it.
Remove mains power switch and fit to new UBA.
Screw the replacement UBA into position.
Reconnect all plug-in cables to their correct sockets.
Fit the casing.
Connect system to mains power supply.
Move mains power switch to "I".
Subject to modifications resulting from technical improvements !
Installation and servicing instructions condensing gas boiler 800 - 24/29/43/60 and 800 - 24T25/29T25 H/V • edition 02/2006
fig. 56 Checking combustion air/flue gas system and
hose connections
fig. 57 Replacing the UBA
Servicing 5
Buderus • http://buderus-domestic.co.uk
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